Wavetable synthesis is used in digital musical instruments (synthesizers) to produce natural tone-like sounds. The sound of a existing instrument (a single note) is sampled and parsed into a sequence of wavetables having one period or cycle in each wavetable. Upon playback, these wavetables are used for sample "lookup" in the same manner as in a Numerically-controlled oscillator (or a Digitally controlled oscillator) but in wavetable synthesis, the output waveform is not normally static and evolves slowly in time as one wavetable is mixed with another, creating a changing waveform. Looping occurs when the wavetable evolution is halted, slowed, or reversed in time. A musical instrument is a device that has been constructed or modified with the purpose of making music. ... A classic FM synthesizer, the Yamaha DX7. ... The Nyquist-Shannon sampling theorem is the fundamental theorem in the field of information theory, in particular telecommunications. ... A numerically controlled oscillator or digitally controlled oscillator (DCO) is an electronic system for synthesizing a range of frequencies from a fixed timebase. ... A numerically controlled oscillator or digitally controlled oscillator (DCO) is an electronic system for synthesizing a range of frequencies from a fixed timebase. ... Audio mixing is used in sound recording, audio editing and sound systems to balance the relative volume and frequency content of a number of sound sources. ...

Different wavetables can be used for the attack phase (at the beginning of the sound, as the volume increases) and release phase (at the end of the sound, as the volume decreases) of the sound. These are normally very difficult to synthesize with other synthesis techniques, but because these are stored as samples very realistic sounds can be produced with little processing power. The Roland Corporation's series of "Linear Additive" synthesizers such as the D-50 made use of a combination of digitally sampled attack phases. Roland EXR-3 Keyboard Roland Corporation (TYO: 7944) is a manufacturer of electronic musical instruments, electronic equipment and software. ...

Because single samples are somewhat limited for synthesis of new sounds, modern wavetable synthesizers can combine multiple samples or even change the sound with filters.

Because of the low processing power required early synthesizers imitated filters and other expensive synthesis methods by rapidly playing successive wavetables in sequence. If each waveform is a little duller (or brighter) than the previous, a filter effect can be imitated.

Special effects can be achieved by selecting a wavetable at random or in a special pattern from the table on a tempo-tick from a sequencer. But the effects are quite strong and don't sound very natural. Of course this can be used on purpose to give the sound a special "edge". The word sequencer can mean: a microsequencer in a computer CPU a music sequencer in the field of electronic music a DNA sequencer or a protein sequencer in the field of biology Sequencer (album) This is a disambiguation page — a navigational aid which lists other pages that might otherwise share...

Palm's wavetable systems

The German synthesizer designer Wolfgang Palm began experimenting with wavetable synthesis in the late 1970s, with his research realized in PPG's line of synthesizers such as the Wavecomputer, Waveterm, and Wave. Palm's implementation of wavetable synthesis employed an array containing 64 pointers to individual (symmetrical) single-cycle waves stored within the instrument. Usually, only a few pointers to these waves were actually used, spread throughout the breadth of the wavetable. The distinguishing feature of the PPG Wave series was that it would interpolate the remaining waves in between the defined pointers, so that changing the position within the table would result in a smooth, unique "morphing" effect between the waves. It should be stressed that Palm's wavetable scheme's strength was in its generation of harsh digital sounds and bell-like timbres, not the emulation of acoustic instruments. It was possible to sample a complex sound into a wavetable by way of the Waveterm device, but the results were invariably artificial, and usually not as interesting as the powerful and bizarre sounds resulting from competent exploitation of the synthesizer's capabilities. This article provides extensive lists of events and significant personalities of the 1970s. ...

After the demise of the PPG company, Waldorf Music adapted Palm's wavetable oscillator design into their wildly successful Microwave synthesizer module (1988). This design was extrapolated into the Waldorf Wave in the early 1990s, a very large and expensive instrument offering facilities for resynthesis and user-friendly wave and wavetable construction. An all-digital revision of the Microwave soon followed, with a complete line of wavetable synthesizers remaining in production until 2003. Aside from a few improvements designed to eliminate audible aliasing and quantization (signal processing) errors, this wavetable oscillator scheme had not significantly changed since the first days of the PPG wave series. Waldorf Music AG is a now insolvent german synthesizer company with some very well known products. ... 1988 is a leap year starting on a Friday of the Gregorian calendar. ... // Events and trends The 1990s are generally classified as having moved slightly away from the more conservative 1980s, but otherwise retaining the same mindset. ... In statistics, signal processing, and related disciplines, aliasing is an effect that causes different continuous signals to become indistinguishable (or aliases of one another) when sampled. ... Quantization of x using Q(x) = floor(Lx)/L. In digital signal processing, quantization is the process of approximating a continuous signal by a set of discrete symbols or integer values; that is, converting an analog signal to a digital one via analog-to-digital conversion. ...

Relation to sample playback

A common misdefinition of the term "wavetable synthesis" is that of any one of many sample based playback devices in popular soundcards and sampling keyboards. The term "sample playback" was deemed inadequate, from a marketing perspective, and the term "wavetable synthesis" was borrowed for use for these soundcards and keyboards. The difference between straight-through sample playback and wavetable synthesis as defined here is that the wave is not kept as a single PCM recording, but as a series of single-cycle waves (or, on later equipment like the Roland D-50, very short PCM samples) that can be played in any order or even omitted. A sound card is a computer expansion card that can input and output sound under program control. ... An AKAI MPC2000 sampler A sampler is an electronic musical instrument that can record and store audio signal samples, generally recordings of existing sounds, and play them back at a range of pitches. ... The polyphonic, 61-key, Roland D50 was released in 1987 to compete on the Yamaha DX7 market. ...

Early sampling keyboards and PC soundcards usually did not work in this mode; before about 1990, limitations in sample memory and computational power meant that samplers and PC trackers could only handle 1 relatively long PCM sample per instrument. Since General MIDI didn't call for anything more sophisticated, and crossfading 3 or more samples per note in tracker-style software was still prohibitively slow at the time, most manufacturers (with the notable exception of Roland's MT-32) decided to stick to this simple method even when better hardware was available. More modern sound cards like the Sound Blaster Live! have multiple independent DCOs that are completely programmable, making Palm-style wavetable effects possible; also, modern PCs have improved in speed and capabilities to the point that using more than one sample per note in a software synthesizer is much easier, though rarely done outside of professional audio software. 1990 is a common year starting on Monday of the Gregorian calendar. ... Tracker is the generic term for a class of software music sequencers which, in their purest form, allow the user to arrange sound samples stepwise on a timeline across several monophonic channels. ... General MIDI - Wikipedia /**/ @import /skins-1. ... The Roland MT-32 is a MIDI synthesizer module first released in 1987 by the Roland Corporation. ... The Sound Blaster family of sound cards was for many years the de facto standard for audio on the IBM PC compatible system platform, before PC audio became commoditized. ... A numerically controlled oscillator or digitally controlled oscillator (DCO) is an electronic system for synthesizing a range of frequencies from a fixed timebase. ... // Software synthesizers A software synthesizer or virtual instrument is a computer program for digital audio generation. ...

The description of wavetable synthesis above is the most original definition and it should be noted (shown in the reference below) that wavetable synthesis is equivalent to additive synthesis in the case that all partials or overtones are harmonic (that is all overtones are at frequencies that are an integer multiple of a fundamental frequency of the tone). Additive synthesis is a technique of audio synthesis which creates musical timbre. ... An overtone is a sinusoidal component of a waveform, of greater frequency than its fundamental frequency. ... An overtone is a sinusoidal component of a waveform, of greater frequency than its fundamental frequency. ... In acoustics and telecommunication, the harmonic of a wave is a component frequency of the signal that is an integer multiple of the fundamental frequency. ... The fundamental tone often referred to simply as the fundamental, is the lowest frequency in a harmonic series. ...

External links

• Wavetable Synthesis 101, A Fundamental Perspective

See also

• Frequency modulation synthesis
• Subtractive synthesis
• Additive synthesis
• Granular synthesis
• Digital waveguide synthesis
• Physical modelling synthesis